Systems and methods for processing glycerol

ABSTRACT

Systems and methods for processing glycerol into one or more useful products are provided. The method can include decreasing a pH of a mixture comprising glycerol and fatty acids to produce an emulsion comprising a glycerol-rich portion and a fatty acids-rich portion. At least a portion of the glycerol-rich portion can be reacted with at least one of an oxidant and a catalyst at conditions sufficient to produce a reacted product comprising glyceric acid, oxalic acid, glycolic acid, formic acid, or any combination thereof.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of co-pending U.S. patentapplication, having Ser. No. 12/965,521, filed on Dec. 10, 2010, andpublished as U.S. Publication No. 2011/0140032, which claims the benefitof U.S. Provisional Patent Application having Ser. No. 61/285,890, filedon Dec. 11, 2009, which are both incorporated by reference herein.

BACKGROUND

1. Field

Embodiments described herein generally relate to systems and methods forprocessing a glycerol-containing feed. More particularly, suchembodiments relate to systems and methods for processing aglycerol-containing feed into one or more products.

2. Description of the Related Art

The level of biodiesel production, an alternative fuel source, hasincreased significantly in recent years. A byproduct derived from thebiodiesel manufacturing process is glycerol, often referred to as “wasteglycerol,” “crude glycerol,” or “raw glycerol.” For every tonne (metricton) of biodiesel made from vegetable oil, 100 kg of thick viscousglycerol is produced as a byproduct. Europe alone produces around 6.8billion liters of biodiesel, which generates around 680,000 tonnes ofwaste glycerol every year. And the recent and rapid expansion inbiodiesel production has resulted in a global oversupply of wasteglycerol.

Although some of the waste glycerol is purified for pharmaceutical orfood applications, the majority ends up as waste. Waste glycerol istypically incinerated, which is a less than optimal use for a low costand readily available byproduct.

There is a need, therefore, for new systems and methods for processingglycerol into one or more products.

SUMMARY

Systems and methods for processing glycerol into one or more productsare provided. In at least one specific embodiment, the method caninclude decreasing a pH of a mixture comprising glycerol and fatty acidsto produce an emulsion comprising a glycerol-rich portion and a fattyacids-rich portion. At least a portion of the glycerol-rich portion canbe reacted with at least one of an oxidant and a catalyst at conditionssufficient to produce a reacted product comprising glyceric acid, oxalicacid, glycolic acid, formic acid, or any combination thereof. In one ormore embodiments, the glycerol-rich portion can be recovered prior toreacting with the oxidant.

In at least one other specific embodiment, the method can includedecreasing a pH of a biodiesel byproduct comprising fatty acids,glycerol, water, methanol, and one or more inorganic salts to produce anemulsion comprising a glycerol-rich portion and a fatty acids-richportion. At least a portion of the glycerol-rich portion can be reactedwith at least one of an oxidant and a catalyst at conditions sufficientto produce a reacted product comprising glyceric acid, oxalic acid,glycolic acid, formic acid, or any combination thereof. In one or moreembodiments, the glycerol-rich portion can be recovered prior toreacting with the oxidant.

In at least one other specific embodiment, the method can include mixinga biodiesel byproduct with a sufficient amount of an acid to produce amixture having a pH of less than about 5.5, wherein the biodieselbyproduct comprises fatty acids, glycerol, water, methanol, one or moreinorganic salts, and solids, and wherein the acid is not a fatty acid.The mixture can be allowed to separate into a glycerol-rich portion anda fatty acids-rich portion. The glycerol-rich portion can be recovered.At least a portion of the recovered glycerol-rich portion can befiltered to remove at least a portion of the solids. At least a portionof the filtered glycerol-rich portion can be reacted with at least oneof an oxidant and a catalyst at conditions sufficient to produce areacted product comprising glyceric acid, oxalic acid, glycolic acid,formic acid, or any combination thereof. The reacted product can becontacted with a fluid. The reacted product can be used to removeinorganic mineral scale deposits, inhibit the formation of inorganicscales, reduce the freeze point of the fluid, remove hydrates, inhibitthe formation of hydrates, or any combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an illustrative system for processing glycerol, accordingto one or more embodiments described.

FIG. 2 depicts another illustrative system for processing glycerol,according to one or more embodiments described.

DETAILED DESCRIPTION

FIG. 1 depicts an illustrative system 100 for processing glycerol,according to one or more embodiments. A glycerol-containing feed vialine 102 and an acid via line 104 can be introduced to one or moremixers 105, where the two components can be mixed, blended, or otherwisecombined together to produce a mixture. The mixture can be allowed toseparate within the mixer 105 into two or more fractions or portions,including a first portion or glycerol-lean portion and a second portionor glycerol-rich portion.

As used herein, the terms “glycerol-lean portion” and “fatty acids-richportion” are used interchangeably to refer to a mixture or compositionthat has a greater concentration of fatty acids than glycerol.Similarly, the term “glycerol-rich portion” and “fatty acids-leanportion” are used interchangeably to refer to a mixture or compositionthat has a greater concentration of glycerol than fatty acids.

The first portion or glycerol-lean portion via line 106 and the secondportion or glycerol-rich portion via line 108 can be recovered from themixer 105. The recovered glycerol-rich portion via line 108 and anoxidant via line 110 can be introduced to one or more reactors 115 toproduce a reacted product via line 116 and an off-gas via line 118. Oneor more catalysts via line 112 can be introduced to the reactor 115 inlieu of or in addition to the oxidant in line 110.

FIG. 2 depicts another illustrative system 200 for processing glycerol,according to one or more embodiments. The system 200 can include themixer(s) 105 and reactor(s) 115 mentioned above and can further includeone or more particulate separation units or filters 205 to removesolids, one or more separators 210 to remove methanol, and one or moreadditional mixers 230. As discussed above, the glycerol-containing feedvia line 102 and the acid via line 104 can be introduced to the one ormore mixers 105, where the two components can be mixed, blended, orotherwise combined together to produce a mixture and separated into atleast two fractions or portions. A first portion or glycerol-leanportion and a glycerol-rich portion.

If solids are present in the glycerol-rich portion, the glycerol-richportion via line 108 can be introduced to the one or more particulateseparation units or filters 205 to produce a solids-rich product vialine 206 and a filtered glycerol-rich portion having a reducedconcentration of solids via line 208 relative to the glycerol-richportion in line 108. The particulate removal unit or filter 205 can beor include any device capable of separating at least a portion of anysolids contained in the glycerol-rich portion in line 108. Illustrativefilters can include, but are not limited to, rigid or flexible screens,pleated cartridges, melt blown cartridges, woven fabrics, non-wovenfabrics, sintered metals, granular media, membranes, centrifugalseparators, bag filters, strainers, or any combination thereof. Screenscan include wedge-wire screens, weave-wire screens such as square weave,Dutch Weave, and Double Dutch Weave, or any combination thereof.Membranes can include ceramic membranes, polymer membranes, or acombination thereof. The particulate removal unit 205 can separateparticles having a size ranging from a low about 0.1 μm, about 0.5 μm,or about 1 μm to a high of about 3 μm, about 5 μm, about 10 μm, forexample. The particulate removal unit 205 can remove from about 50% toabout 100% of the solids contained in the glycerol-rich portion in line108. For example, the particulate removal unit 205 can remove about 50%,about 60%, about 70%, about 80%, about 90%, or about 95% of the solidscontained in the glycerol-rich portion in line 108.

The filtered glycerol-rich portion via line 208 can be introduced to theone or more separators 210, which can remove or otherwise separatemethanol, if present, in the filtered glycerol-rich portion of line 208.The separated methanol can be recovered via line 212 and a glycerol-richportion having a reduced concentration of methanol can be removed vialine 214. The glycerol-rich portion via line 214 and the oxidant vialine 110 and/or the catalyst via line 112 can be introduced to the oneor more reactors 115 to produce a reacted product (“first product”) vialine 222 and an off-gas via line 118.

As a result of separating methanol within the separator 210, theconcentration of formic acid in the reacted product of line 222 can bereduced relative to the concentration of formic acid in the reactedproduct of line 116 (FIG. 1) since formic acid is a reaction productfrom reacting methanol with the oxidant and/or catalyst in reactor 115.Therefore, removing at least a portion of any methanol, if present, inthe glycerol-rich portion in line 208 can reduce the concentration offormic acid in the reacted product recovered via line 222 relative tothe concentration of formic acid in the reacted product in line 116.

At least a portion of the reacted product of line 222 can be introducedvia line 224 to the one or more additional mixers (“second mixer”) 230where a base compound via line 226 can be mixed, blended, or otherwisecombined with the product from line 224 to produce a second reactedproduct via line 232. Combining the reacted product of line 224 with thebase compound of line 226 can produce a second reacted product via line232 having a higher pH (i.e. more alkaline) than the reacted product ofline 116 (FIG. 1) and/or 222 (FIG. 2). A product with a pH in the rangeof about 5.5 to about 8.0 can be useful as a hydrate inhibitor, and canfacilitate certain gas recovery, as described in more detail below.

Referring to FIGS. 1 and 2, the glycerol-containing feed in line 102 caninclude, but is not limited to, glycerol, monoglycerides, diglycerides,methanol, soaps of fatty acids, fatty acids, organic salts, inorganicsalts, water, biodiesel, solids, or any combination thereof. Theglycerol-containing feed in line 102 can come from any number of sourcesor processes. For example, the glycerol-containing feed via line 102 canbe or include a byproduct from the production of biodiesel. In anotherexample, the glycerol-containing feed can be or include a byproduct fromthe production of soaps, e.g. produced by the saponification of animalfats. In yet another example, the glycerol-containing feed can includeglycerol produced from the conversion of epichlorohydrin. In yet anotherexample, the glycerol-containing feed can be or include a byproduct fromthe refining of cooking and salad oils. Should the glycerol-containingfeed of line 102 be free of fatty acids and soaps of fatty acids, theglycerol-containing feed can bypass the mixer 105 and can be introduceddirectly to the reactor 115.

Dependent on its source of origin, the glycerol-containing feed in line102 can have a pH ranging from a low of about 6, about 6.5, or about 7to a high of about 8, about 9, or about 10, and can include from about 1wt % to about 99 wt % glycerol. The glycerol-containing feed in line 102can also include from about 5 wt % to about 15 wt % methanol, from about5 wt % to about 10 wt % water, from about 20 wt % to about 35 wt % fattyacids and/or soaps of fatty acids, from about 7 wt % to about 15 wt %inorganic and/or organic salts, and/or from about 1 wt % to about 10 wt% solids. The fatty acids can include acyclic and/or aliphaticcarboxylic acids. Such fatty acids can contain any where from about 8 toabout 22 carbon atoms. With respect to carbon-carbon bonds, the fattyacids can be saturated, monounsaturated, or polyunsaturated. The organicsalts can include, but are not limited to, sodium, lithium, salts offatty acids, proteins, or any combination thereof. The inorganic saltscan include, but are not limited to, sodium chloride (NaCl), potassiumchloride (KCl), lithium chloride (LiCl), or any combination thereof. Thesolids can include, but are not limited to, fats, carbons, salts offatty acids, polymers of fatty acids, or any combination thereof.

The acid in line 104 can be or include any acid or combination of two ormore acids. For example, the acid in line 104 can be or include one ormore mineral acids, sulfonic acids, carboxylic acids, or any combinationthereof. Illustrative mineral acids can include, but are not limited to,hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI),hypochloric acid, chloric acid, perchloric acid, periodic acid, sulfuricacid (H₂SO₄), fluorosulfuric acid (FSO₃H), nitric acid (HNO₃),phosphoric acid (H₃PO₄), fluoroantimonic acid (HSbF₆), fluoroboric acid(HBF₄), hexafluorophosphoric acid (HPF₆), and chromic acid (H₂CrO₄).Illustrative sulfonic acids can include, but are not limited to,methanesulfonic acid (MeSO₃H), ethanesulfonic acid (EtSO₃H),benzenesulfonic acid (C₆H₅SO₃H), p-Toluenesulfonic acid (CH₃C₆H₄SO₃H),and trifluoromethanesulfonic acid (CF₃SO₃H). Illustrative carboxylicacids can include, but are not limited to, acetic acid (C₂H₄O₂), citricacid (C₆H₈O₇), formic acid (CH₂O₂), gluconic acid (C₆H₁₂O₇), lactic acid(C₃H₆O₃), oxalic acid (C₂H₂O₄), and tartaric acid (C₄H₆O₆). If the acidin line 104 includes carboxylic acid(s), the number of carbon atoms inthe carboxylic acid(s) is preferably less than 8, or less than 7, orless than 6. In at least one specific embodiment, the acid in line 104can be an acid other than a fatty acid. In at least one specificembodiment, the acid or combination of acids in line 104 is not acarboxylic acid. In at least one specific embodiment, the acid orcombination of acids in line 104 is not a fatty acid.

The acid in line 104 can be introduced to the mixer 105 in an amountsufficient to produce a mixture therein having a pH of less than about5.5, less than about 5, less than about 4.5, or less than about 4. Forexample, the pH of the mixture can range from a low of about 2.5, about3, or about 3.5 to a high of about 4, about 4.5, or about 5. Theparticular amount and/or type of acid added to the mixer 105 can depend,at least in part, on the amount of the glycerol or the fatty acids inthe glycerol-containing feed and the pH of the feed. For example, 1 to100 moles of acid can be added per mole of glycerol-containing feed tomeet the desired pH of the resulting mixture. The amount of acid addedto the glycerol-containing feed can also range anywhere from about 1:1to about 90:1; about 5:1 to about 75:1; or about 10:1 to about 20:1, ona volume basis.

The mixer 105 can be any device or system suitable for batch,intermittent, and/or continuous mixing, blending, or otherwise combiningof two or more components. For example, the mixer 105 can be any deviceor system suitable for mixing the glycerol-containing feed in line 102and the acid in line 104. The mixer 105 can be capable of producing ahomogenized mixture. Illustrative mixers can include, but are notlimited to, mechanical mixer agitation, ejectors, static mixers,mechanical/power mixers, shear mixers, sonic mixers, or combinationsthereof. The mixer 105 can include one or more heating jackets, heatingcoils, internal heating elements, or the like, to regulate thetemperature therein.

Decreasing the pH of the glycerol-containing feed in line 105 by mixing,blending, or otherwise combining the one or more acids of line 104therewith facilitates the separation of the glycerol from theglycerol-containing feed. The lower pH forms an emulsion of a firstlayer or “glycerol-lean portion” and a second layer or “glycerol-richportion.” The first layer can also be referred to as a “fatty acids-richportion,” and can include the fatty acids, soaps of fatty acids, and/orbiodiesel from the glycerol-containing feed. The glycerol-rich portioncan include the glycerol, monoglycerides, diglycerides, methanol,organic salts, inorganic salts, and/or water from theglycerol-containing feed.

In one or more embodiments, the mixture of the glycerol-containing feedand the acid in the mixer 105 can be heated to accelerate the combiningand separation process. For example, the mixture can be heated to atemperature of about 40° C., about 50° C., about 55° C., about 60° C.,or about 65° C. If methanol is present and it is desirable to maintainmethanol in the glycerol-rich portion of line 108, the temperature canbe maintained below about 64.7° C., which is the boiling point ofmethanol. In at least one specific embodiment, the mixture can be heatedto a temperature greater than about 65° C., to vaporize the methanol, ifpresent, in the glycerol-containing feed in line 102. As such, if theglycerol-containing feed includes methanol, the methanol can either berecovered as a separate product or the methanol can remain in theglycerol-rich portion recovered via line 108 by regulating thetemperature of the mixer 105. Although not shown, methanol can berecovered or separated from the feed 102 prior to the mixer 105 toproduce a methanol-lean glycerol-containing feed in line 102.

The glycerol-rich portion in line 108 can have a glycerol concentrationranging from a low of about 30 wt %, about 40 wt %, or about 45 wt % toa high of about 55 wt %, about 60 wt %, about 65 wt %, about 75 wt %,about 85 wt %, or about 95 wt %. The glycerol-rich portion in line 108can have a methanol concentration ranging from a low of about 1 wt %,about 5 wt %, or about 10 wt % to a high of about 25 wt %, about 30 wt%, or about 35 wt %. The glycerol-rich portion in line 108 can have awater concentration ranging from a low of about 5 wt %, about 10 wt %,or about 12 wt % to a high of about 15 wt %, about 20 wt %, or about 25wt %. The glycerol-rich portion in line 108 can have a saltconcentration ranging from a low of about 0.5 wt %, about 1 wt %, orabout 2 wt % to a high of about 5 wt %, about 7 wt %, or about 9 wt %.The glycerol-rich portion in line 108 can have a solids concentrationranging from a low of about 0.5 wt %, about 1 wt %, or about 3 wt % to ahigh of about 5 wt %, about 10 wt %, or about 15 wt %. The glycerol-richportion in line 108 can also include residual or trace amounts ofmonoglycerides, proteins, amino acids, and/or gums, for example. Theglycerol-rich portion in line 108 can have a fatty acids concentrationof less than about 15 wt %, less than about 10 wt %, less than about 5wt %, less than about 3 wt %, less than about 1 wt %, or less than about0.5 wt %.

The oxidant in line 110 can include one or more oxidants including, butnot limited to, hydrogen peroxide (H₂O₂), oxygen (O₂), ozone (O₃),oxygen-containing gases, e.g., air, sodium permanganate, potassiumpermanganate, sodium persulfate, potassium persulfate, magnesiumperoxide, calcium peroxide, sodium percarbonate, or any combinationsthereof. The amount of oxidant introduced via line 110 to the reactor115 can vary, but should be sufficient to at least partially oxidize theglycerol-rich portion introduced via line 108. The amount of oxidant candepend, at least in part, on the amount of the glycerol in the reactor115 and/or the particular composition or make-up of the glycerol in line108. In one or more embodiments, the amount of the oxidant introducedvia line 110 can be based on the number of moles of oxidant per mole ofglycerol and can range from a low of about 0.2 mol %, about 0.4 mol %,about 0.5 mol %, or about 0.8 mol % to a high of about 1 mol %, about1.2 mol %, about 1.5 mol %, or about 2 mol %.

The reactor 115 can be any container or environment suitable for batch,intermittent, and/or continuous contact of the glycerol-rich portion ofline 108 with the oxidant of line 110 and/or the catalyst of line 112.In one or more embodiments, the reactor 115 can be an open vessel or aclosed vessel. In one or more embodiments, the reactor 115 can includeone or more mixing devices such as one or more mechanical/power mixersand/or sonic mixers. In one or more embodiments, the reactor 115 caninclude a cooling jacket and/or coil for maintaining a temperature ofthe reaction mixture at a predetermined temperature. The reactor 115 caninclude one or more nozzles, fluid distribution grids, or otherdevice(s) for introducing the oxidant to the reactor 110.

Within the reactor 115, at least a portion of the glycerol can reactwith the oxidant at conditions sufficient to produce glyceric acid,oxalic acid, glycolic acid, formic acid, glyceraldehydes, hydroxypyruvicacid, tartronic acid, derivatives thereof, or any combination thereof.In one or more embodiments, at least a portion of the methanol, ifpresent, can react with the oxidant at conditions sufficient to produceformic acid. Suitable conditions include a temperature of about 70° C.or less, about 65° C. or less, about 60° C. or less, or about 55° C. orless. The reaction temperature can also range from a low of about 0° C.,15° C., or 20° C. to a high of about 50° C., 65° C., or 75° C., althoughhigher temperatures are envisaged.

The one or more catalysts via line 112 can be introduced to the reactor115, in addition to or in lieu of the oxidant via line 110, to producethe reacted product via line 116. Suitable catalysts can include, butare not limited to, platinum, palladium, carbon supported platinum,potassium permanganate, chromium oxide, carbon supported palladium,silicates, aluminophosphates, or any combination thereof. In at leastone specific embodiment, hydrogen peroxide via line 110 and/or acatalyst, e.g., ferrous sulfate and/or potassium permanganate, via line112 can be introduced to the reactor 115.

The composition or make-up of the reacted product in line 116 can widelyvary. The amount of oxidant and/or catalyst, residence time,temperature, pressure, and other process variables can influence theparticular products and the relative amounts of those particularproducts produced. For example, increasing the temperature of thereaction mixture can increase the amount of acids, e.g., carboxylicacids, produced in the reactor 115 and contained in the reacted productin line 116. In another example, increasing the amount of oxidant,relative to the amount of the glycerol-rich portion, can increase theamount of acids, e.g., carboxylic acids, produced in the reactor 115 andcontained in the reacted product in line 116.

The reacted product in line 116 can have a concentration of glycericacid ranging from a low of about 1 wt %, about 10 wt %, or about 20 wt %to a high of 50 wt %, about 60 wt %, about 70 wt %, about 80 wt %, orabout 100 wt %. The reacted product in line 116 can also have aconcentration of oxalic acid ranging from a low of about 0.1 wt %, about1 wt %, or about 3 wt % to a high of about 5 wt %, about 7 wt %, orabout 10 wt %. The reacted product in line 116 can also have aconcentration of glycolic acid ranging from a low of about 0.1 wt %,about 0.5 wt %, or about 1 wt % to a high of about 1.5 wt %, about 2 wt%, or about 3 wt %. The reacted product in line 116 can also have aconcentration of formic acid ranging from a low of about 1 wt %, about 5wt %, or about 10 wt % to a high of about 20 wt %, about 30 wt %, orabout 40 wt %. The reacted product in line 116 can also have aconcentration of glyceraldehydes ranging from a low of about 0.1 wt %,about 0.5 wt %, or about 1 wt % to a high of about 1.5 wt %, about 2 wt%, or about 3 wt %. The reacted product in line 116 can also have aconcentration of hydroxypyruvic acid ranging from a low of about 0.1 wt%, about 1 wt %, or about 1.5 wt % to a high of about 3 wt %, about 5 wt%, or about 7 wt %. The reacted product in line 116 can also have aconcentration of tartronic acid ranging from a low of about 0.1 wt %,about 0.5 wt %, or about 1 wt % to a high of about 1.5 wt %, about 2 wt%, or about 3 wt %. The reacted product in line 116 can also have aconcentration of water ranging from a low of about 1 wt %, about 5 wt %,or about 10 wt % to a high of about 30 wt %, about 40 wt %, or about 50wt %. The reacted product in line 116 can also have a concentration ofsolids ranging from a low of about 0.1 wt %, about 0.5 wt %, or about 1wt % to a high of about 1.5 wt %, about 2 wt %, or about 3 wt %. Thereacted product in line 116 can also have a concentration of glycerolranging from a low of about 0.1 wt %, about 5 wt %, or about 10 wt % toa high of about 20 wt %, about 30 wt %, or about 40 wt %. The reactedproduct in line 116 can also have a concentration of methanol rangingfrom a low of about 0.1 wt %, about 1 wt %, or about 3 wt % to a high ofabout 5 wt %, about 7 wt %, or about 10 wt %.

Considering the separator 210 of FIG. 2 in more detail, the separator210 can be empty, partially filled, or completely filled with one ormore trays and/or packing to improve mass transfer and/or separation ofa multi-component fluid. Illustrative trays can include, but are notlimited to, perforated trays, sieve trays, bubble cap trays, floatingvalve trays, fixed valve trays, tunnel trays, cartridge trays, dual flowtrays, baffle trays, shower deck trays, disc and donut trays, orbittrays, horse shoe trays, cartridge trays, snap-in valve trays, chimneytrays, slit trays, or any combination thereof.

The packing can increase the effective surface area, which can improvethe mass transfer therein. Suitable packing can include, but is notlimited to, metals, non-metals, polymers, ceramics, glasses, or anycombination thereof. The packing can be structured and/or random.Suitable structured packing can include Raschig rings, Lessing rings,I-rings, saddle rings, Berl saddles, Intalox saddles, Tellerettes, Pallrings, U-rings, or any combination thereof. Illustrative examples ofcommercially available structured packing can include, but is notlimited to FLEXIPAC® and GEMPAK® structured packing as manufactured bythe Koch-Glitsch Corporation, corrugated sheets, crimped sheets, gauzes,grids, wire mesh, monolith honeycomb structures, or any combinationthereof.

The separator 210 can be used to separate at least a portion of themethanol, if present, in the glycerol-rich portion in line 208 toprovide the methanol via line 212 and the glycerol-rich portion via line214. The separated glycerol-rich portion via line 214 can have a reducedconcentration of methanol relative to the glycerol-rich portion in line208. The separator 210 can include any number of separation processes,for example, evaporation, fractionation, and/or distillation. In one ormore embodiments, all or a portion of the methanol contained in theglycerol-rich portion in line 208 can be separated and recovered vialine 212. As such, the glycerol-rich portion recovered via line 214 caninclude less than about 30 wt %, less than about 20 wt %, less thanabout 10 wt %, less than about 5 wt %, less than about 2 wt %, less thanabout 1 wt %, less than about 0.5 wt %, or less than about 0.1 wt %methanol.

The base compound of line 226 that is added to mixer(s) 230 can be orinclude any base or combination of two or more bases. Illustrative basesor base compounds can include, but are not limited to, potassiumhydroxide (KOH), sodium hydroxide (NaOH), lithium hydroxide (LiOH),amines, or any combination thereof. Suitable amines can include, but arenot limited to, alkanolamines, polyamines, aromatic amines, and anycombination thereof. Illustrative alkanolamines can include, but are notlimited to, monoethanolamine (MEA), diethanolamine (DEA),triethanolamine (TEA), or any combination thereof. Illustrative aromaticamines can include, but are not limited to, benzyl amine, aniline, orthotoludine, meta toludine, para toludine, n-methyl aniline, N-N′-dimethylaniline, di- and tri-phenyl amines, 1-naphthylamine, 2-naphthylamine,4-aminophenol, 3-aminophenol and 2-aminophenol. Illustrative polyaminescan include, but are not limited to, diethylenetriamine (DETA),triethylenetetramine (TETA), tetraethylenepentamine (TEPA)1,3-propanediamine, 1,4-butanediamine, polyamidoamines, andpolyethylenimines.

The particular amount of the base compound added can depend, at least inpart, on the amount of the particular composition or make-up of thereacted product, i.e. the particular components and the relative amountof those components contained in the reacted product of line 224. In oneor more embodiments, the base compound in line 226 can be introduced tothe second mixer 230 in an amount sufficient to produce a mixturetherein having a pH of about 6 or more, about 6.5 or more, about 7 ormore, about 7.5 or more, about 8 or more, about 8.5 or more. Forexample, the pH of the mixture within the second mixer 230 can rangefrom a low of about 6, about 6.5, or about 7 to a high of about 8, about8.5, or about 9. In another example, about 1 to about 100 moles of basecan be added per mole of reacted product to meet the desired pH of theresulting mixture in line 232. The amount of base added to the reactedproduct can also range anywhere from about 1:1 to about 90:1, about 5:1to about 75:1, or about 10:1 to about 20:1, on a volume basis.

The reacted products, i.e. the reacted product in lines 116, 222, and/orthe second reacted product in line 232, can have a flash point greaterthan about 30° C., greater than about 38° C., greater than about 50° C.,greater than about 66° C., or greater than about 93° C. and less thanabout 300° C., less than about 250° C., or less than about 200° C. Forexample, the reacted products can have a flash point of about 32° C.,about 54° C., about 60° C., about 68° C., about 75° C., or about 95° C.The reacted products can have a freezing point of less than about −25°C., less than about −50° C., less than about −60° C., or less than about−65° C.

The reacted products can also have a specific gravity, relative todemineralized water, ranging from a low of about 1.05, about 1.09, orabout 1.15 to a high of about 1.3, about 1.4, or about 1.5. For example,the reacted products can have a specific gravity, with respect todemineralized water, of about 1.1, about 1.2, about 1.25, or about 1.3.

The reacted products can also have a pH of less than about 3.5, lessthan about 3, less than about 2.5, less than about 2, less than about1.5, or less than about 1. The pH of the reacted products can also rangefrom a low of about 1, about 1.3, about 1.7, or about 2.1 to a high ofabout 3, about 3.3, about 3.6, or about 3.9.

The reacted products, i.e. the reacted product of lines 116, 222, and/orthe second reacted product of line 232, can be mixed or blended withcorrosion inhibitors, polymers, salts, scale removers, surfactants,inhibitors, or any combination thereof and can be used in any number ofapplications. Illustrative corrosion inhibitors can include, but are notlimited to, filmers, neutralizers, or a combination thereof.Illustrative polymers can include, but are not limited to, polyols,polyamides, poly celluloses, poly(acrylic acids), or any combinationthereof. Illustrative salts can include, but are not limited to, NaCl,KCl, LiCl, trisodium phosphate (TSP), sodium tripolyphosphate or sodiumtriphosphate (STPP or STP), tripotassium phosphate (TKPP), potassiumtriphosphate (KTP), or any combination thereof.

In one or more embodiments, the reacted products of lines 116, 222,and/or 232 can act or work as an acid, a sequestrant, a chelant, adispersing agent, a solvent, or any combination thereof for removingmineral scale deposits (scale). The formation of scales can be caused bya number of factors, which can include, but are not limited Co, pressuredrops, temperature fluctuations, changes in pH or ionic strength, andany combinations thereof. The formation or precipitation of scaledeposits can occur in, for example, oil production and/or processingequipment, which can be located above and/or below the surface. Theformation or precipitation of scale deposits can also occur insubterranean formations, such as an oil and/or gas producing formations.Oil production and processing equipment can include, flow lines,heaters, pumps, valves, pipes, pipelines, risers, drill strings,wellbores, downhole pumps, perforations, fractures, fissures, and thelike. Other areas in which scale deposits can be problematic include,but are not limited to, the chemical processing industries, publicutilities, and other processes in which mineral-laden water is processedor used, as in heat exchangers, storage vessels, piping, reactors,evaporators, and the like. Commonly encountered scales include, but arenot limited to, calcium carbonate (CaCO₃), calcium sulfate (CaSO₄),barium sulfate (BaSO₄); and sodium chloride (NaCl). Other inorganicmineral deposits can include, strontium sulfate (SrSO₄), strontiumcarbonate (SrCO₃), iron oxide (Fe₂O₃), iron carbonate (FeCO₃), ironsulfide (FeS), barium-strontium sulfate (BaSr(SO₄)₂), magnesiumcarbonate (MgCO₃), magnesium sulfate (MgSO₄), or any combinationthereof.

Introducing the reacted products in lines 116, 222, and/or 232 toequipment, formations, and/or other locations where scale deposits formor can potentially form can reduce scale and/or inhibit or prevent theformation of scale. The reacted products, at any desired concentration,can be used to remove scale and/or prevent or reduce the formation ofscale. In one or more embodiments, the reacted products in lines 116,222, and/or 232 can be diluted with water to provide an aqueous solutionhaving a desired concentration.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used to demulsify an emulsion. The reacted products,for example, can demulsify an emulsion by lowering the pH of theemulsion and/or by increasing the specific gravity of the producedwater. The reacted products can be used as produced, diluted, and/ormixed with other ingredients that can improve the demulsification.Illustrative additional ingredients can include, but are not limited to,silicon compounds, glycols, salts, any other water soluble demulsifiers,or any combination thereof.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used as a frac fluid, drilling fluid, or componentthereof for oil and/or gas production. The reacted products in lines116, 222, and/or 232 can be used neat or mixed or blended with one ormore other fluids. An illustrative frac fluid, for example, can includeabout 5 wt % to about 25 wt % reacted product, about 5 wt % to about 25wt % formic acid, and about 45 wt % to about 65 wt % water. Illustrativeblending agents and/or additives can include, but are not limited to,drilling fluids, steam, corrosion inhibitors, water, acids such ashydrochloric acid, surfactants, polymers such as polyols, polyamides,poly celluloses, poly(acrylic acids), or any combination thereof. Fordrilling, the reacted product is particularly useful in water-baseddrilling fluids.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used as an anti-icing compound. The reacted productscan be used neat, diluted with water, and/or or blended with one or moreadditives. In at least one specific embodiment, the anti-icing compoundcan be sprayed, injected, or otherwise introduced on or to pipelines,processing equipment, diluents for chemicals, storage tanks, ships, oilrigs, trucks, and storage equipment, for example.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used as a general purpose cleaner. As a generalpurpose cleaner, the reacted products can be used neat, diluted withwater, and/or blended with one or more additives. Suitable additives caninclude, but are not limited to, polymers, salts, and/or other treatmentchemicals that can expand or enhance one or more functional propertiesof the reacted products. In at least one specific embodiment, thereacted products can be diluted with water to provide a cleaningsolution having a concentration of the reacted product ranging fromabout 100 ppmw to about 40 wt %.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used to prevent or reduce the formation of hydrates ina fluid containing one or more hydrate-forming constituents bycontacting the fluid with the reacted product(s). For example, thesecond reacted product via line 232 can be introduced to a fluid orsystem that contains hydrates or in which hydrates can potentially form,e.g., a hydrocarbon gas stream containing methane and/or natural gas.Illustrative systems can include, but are not limited to, hydrocarbonproduction/processing equipment, pipelines, storage tanks, and the like.In at least one specific embodiment, the reacted products can beintroduced into a downhole location such as a hydrocarbon productionwell to control hydrate formation in fluids produced therefrom. Inanother example, the reacted products can be introduced to a producedhydrocarbon at a wellhead location or into a riser through whichproduced hydrocarbons are transported in offshore operations from theocean floor to an offshore production facility. In still anotherexample, the reacted products can be introduced to a hydrocarbon priorto transporting the hydrocarbon, for example, via a subsea pipeline froman offshore production facility to an onshore gathering and/orprocessing facility. In one or more embodiments, the reacted productscan be introduced to a downhole location as a drilling fluid or as acomponent of a drilling fluid.

In one or more embodiments, the reacted products in lines 116, 222,and/or 232 can be used to recover a gas that is bound or entrained in aformed hydrate. In at least one specific embodiment, the second reactedproduct via line 232 can be introduced into a downhole location or anyother location that contains or may contain hydrates where the secondreacted product can release at least a portion of any gases bound orcontained in the hydrate(s) present therein. The released gases bound inthe hydrate(s) can be recovered as a product.

A mixture that can potentially form or contain hydrates can include, forexample a water and gas mixture. The gas can be a hydrocarbon normallygaseous at 25° C. and 100 kPa, such as an alkane of 1-4 carbon atoms,e.g., methane, ethane, propane, n-butane, isobutane, or an alkene of 2-4carbon atoms, e.g., ethylene, propylene, n-butene, isobutene, or anycombination thereof. The gas can include about 80 wt %, about 90 wt %,or more methane. The gas can also include about 0.1 wt % to about 10 wt% C₂ hydrocarbons and about 0.01 wt % to about 10 wt % C₃ hydrocarbons.

EXAMPLES

In order to provide a better understanding of the foregoing discussion,the following non-limiting examples are offered. Although the examplesmay be directed to specific embodiments, they are not to be viewed aslimiting the invention in any specific respect. All parts, proportions,and percentages are by weight unless otherwise indicated.

Example I

In Example I, an existing well (Well A) that could be produced twice aday for an hour (on pump) for a total of about 4 to about 6 bbls offluid per day before pumping off was evaluated. A produced water from adifferent well/different zone was introduced into Well A. The result wasan immense calcium carbonate problem. The well had to be completely shutdown due to calcium carbonate scaling within the production line as wellas near the wellbore and within the formation. More water was attemptedto be introduced/forced into the formation in an attempt to open theformation. The well was pressured up to about 4,500 psi but no morewater flowed into the formation.

A three hundred (300) gallon “pill” of a reacted product was introducedinto the Well A. The reacted product or pill was prepared according tothe following process: a biodiesel waste product was mixed with asufficient amount of hydrochloric acid (HCl) to adjust the pH to about 3at room temperature and pressure. The mixture was allowed to separateinto a glycerol-rich portion and a fatty acids-rich portion. The fattyacids-rich portion was then separated from the glycerol-rich portion. A30 wt % hydrogen peroxide solution was then added to and reacted withthe glycerol-rich portion to produce the reacted product. The amount ofhydrogen peroxide added to the glycerol-rich portion was about 10 wt %,based on the total weight of the glycerol-rich portion. From the reactedproduct, the three hundred gallon pill was acquired.

The three hundred gallon pill was then introduced into Well A via a pumptruck. After introduction of the pill, Well Awns pressured up to about1,750 psi and then shut in. After about 1.5 hours, the pressure on WellA was about 0 psi. Well A was left shut in for about 48 hours, afterwhich time Well A was brought back on line. After bringing Well A backon line, about 65+ bbls of total fluid/day were produced with nostoppage. The oil production fluctuated between about 15 bbls per dayand about 25 bbls per day.

Example II

In Example II, a second well (Well B) was producing about 65 bbls perday and had a bottom hole temperature of about 130° F. to about 150° F.The well was treated with another produced water, similar to Example Iabove, i.e. produced water from another well/zone, and production fromthe well dropped to about 0.4 bbls of total fluid per day. Well B couldonly be pumped for about 5 hours before pumping off.

A 503 gallon pill of the same reacted product used in Example I wasintroduced into Well B. The pill was introduced at 10:17 AM and at 10:24AM, pressuring up of the well was started. At 10:52 AM the final amountof the pill was introduced and Well B was shut in and had a pressure ofabout 1,300 psi. At 10:54 AM a bullplug was put into the well and thepressure on the well was down to about 1,000 psi. At 11:25 AM thepressure of the still shut in well was about 0 psi. The following daythe well was under a vacuum. An operator began pulling on the well withgreat returns. The returns, after sending the pill into Well B, wasgreater than 85 bbls of total fluid/day.

Example III

In Example III, a third well (Well C) that began building pressure wastreated. Well C was a disposal well for disposing of salt water. It wasdetermined that the pressure in Well C was building due to tank bottoms.A 500 gallon pill of the same reacted product used in Example 1 wasintroduced into Well C and after about 2 hours, the pressure droppedabout 200 psi and additional salt water could again be injected intoWell C.

Certain embodiments and features have been described using a set ofnumerical upper limits and a set of numerical lower limits. It should beappreciated that ranges from any lower limit to any upper limit arecontemplated unless otherwise indicated. Certain lower limits, upperlimits and ranges appear in one or more claims below. All numericalvalues are “about” or “approximately” the indicated value, and take intoaccount experimental error and variations that would be expected by aperson having ordinary skill in the art.

Various terms have been defined above. To the extent a term used in aclaim is not defined above, it should be given the broadest definitionpersons in the pertinent art have given that term as reflected in atleast one printed publication or issued patent. Furthermore, allpatents, test procedures, and other documents cited in this applicationare fully incorporated by reference to the extent such disclosure is notinconsistent with this application and for all jurisdictions in whichsuch incorporation is permitted.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A method comprising, removing one or more inorganic mineral scales bycontacting the one or more inorganic mineral scales with a compositioncomprising about 1 wt % to about 80 wt % glyceric acid, about 0.1 wt %to about 10 wt % oxalic acid, about 0.1 wt % to about 3 wt % glycolicacid, and about 1 wt % to about 40 wt % formic acid.
 2. The method ofclaim 1, wherein the one or more inorganic mineral scales is selectedfrom the group consisting of calcium carbonate, calcium sulfate, bariumsulfate, sodium chloride, strontium sulfate, strontium carbonate, ironoxide, iron carbonate, iron sulfide, barium-strontium sulfate, magnesiumcarbonate, magnesium sulfate, and any combination thereof.
 3. The methodof claim 1, wherein the composition further comprises about 0.1 wt % toabout 3 wt % glyceraldehydes.
 4. The method of claim 1, wherein thecomposition further comprises about 0.1 wt % to about 7 wt %hydroxypyruvic acid.
 5. The method of claim 1, wherein the compositionfurther comprises about 0.1 wt % to about 3 wt % tartronic acid.
 6. Themethod of claim 1, wherein the composition further comprises about 0.1wt % to about 40 wt % glycerol.
 7. The method of claim 1, wherein thecomposition further comprises about 0.1 wt % to about 10 wt % methanol.8. The method of claim 1, wherein the composition further comprisesabout 1 wt % to about 50 wt % water.
 9. The method of claim 1, whereinthe composition comprises about 10 wt % to about 80 wt % glyceric acid,about 3 wt % to about 10 wt % oxalic acid, about 0.5 wt % to about 3 wt% glycolic acid, and about 5 wt % to about 40 wt % formic acid, andwherein the composition further comprises about 10 wt % to about 50 wt %water.
 10. The method of claim 1, wherein the composition furthercomprises at least two of: about 0.1 wt % to about 3 wt %glyceraldehydes, about 0.1 wt % to about 7 wt % hydroxypyruvic acid,about 0.1 wt % to about 3 wt % tartronic acid, about 0.1 wt % to about40 wt % glycerol, and about 1 wt % to about 50 wt % water.
 11. Themethod of claim 1, wherein the composition has a flash point of about30° C. to about 300° C., a freeze point less than about −25° C., and aspecific gravity relative to demineralized water of about 1.05 to about1.5.
 12. The method of claim 1, wherein the composition has a pH lessthan about 3.5, and the method further comprises increasing the pH ofthe composition to about 6 to about 9 by combining one or more basecompounds with the composition prior to contacting the one or moreinorganic mineral scales with the composition.
 13. A method comprising:demulsifying an emulsion by mixing the emulsion with a composition;fracturing a hydrocarbon bearing formation using the composition;lowering a freeze point of water using the composition; or using thecomposition in a wellbore as a drilling fluid or as a component of adrilling fluid, wherein the composition comprises about 1 wt % to about80 wt % glyceric acid, about 0.1 wt % to about 10 wt % oxalic acid,about 0.1 wt % to about 3 wt % glycolic acid, and about 1 wt % to about40 wt % formic acid.
 14. The method of claim 13, wherein the compositioncomprises about 10 wt % to about 80 wt % glyceric acid, about 3 wt % toabout 10 wt % oxalic acid, about 0.5 wt % to about 3 wt % glycolic acid,about 5 wt % to about 40 wt % formic acid, and wherein the compositionfurther comprises about 1 wt % to about 50 wt % water.
 15. The method ofclaim 13, wherein the composition further comprises at least two of:about 0.1 wt % to about 3 wt % glyceraldehydes, about 0.1 wt % to about7 wt % hydroxypyruvic acid, about 0.1 wt % to about 3 wt % tartronicacid, about 0.1 wt % to about 40 wt % glycerol, and about 1 wt % toabout 50 wt % water.
 16. A method comprising, contacting a fluid with acomposition comprising about 1 wt % to about 80 wt % glyceric acid,about 0.1 wt % to about 10 wt % oxalic acid, about 0.1 wt % to about 3wt % glycolic acid, and about 1 wt % to about 40 wt % formic acid,wherein by contacting with the fluid, the composition: (1) removes atleast a portion of one or more inorganic mineral scale depositscontained in the fluid, (2) inhibits a formation of one or moreinorganic scales in the fluid, (3) reduces a freeze point of the fluid,(4) removes at least a portion of one or more hydrates contained in thefluid, (5) inhibits a formation of one or more hydrates in the fluid, or(6) any combination thereof.
 17. The method of claim 16, wherein thecomposition has a pH less than about 3.5, and the method furthercomprises increasing the pH of the composition to about 6 to about 9 bycombining one or more base compounds with the composition prior tocontacting the fluid with the composition.
 18. The method of claim 16,wherein the composition comprises about 10 wt % to about 80 wt %glyceric acid, about 3 wt % to about 10 wt % oxalic acid, about 0.5 wt %to about 3 wt % glycolic acid, about 5 wt % to about 40 wt % formicacid, and wherein the composition further comprises about 1 wt % toabout 50 wt % water.
 19. The method of claim 16, wherein the compositionfurther comprises at least two of: about 0.5 wt % to about 3 wt %glyceraldehydes, about 1 wt % to about 7 wt % hydroxypyruvic acid, about0.5 wt % to about 3 wt % tartronic acid, and about 5 wt % to about 40 wt% glycerol.
 20. The method of claim 16, wherein the composition furthercomprises about 0.1 wt % to about 3 wt % glyceraldehydes, about 0.1 wt %to about 7 wt % hydroxypyruvic acid, about 0.1 wt % to about 3 wt %tartronic acid, about 0.1 wt % to about 40 wt % glycerol, and about 1 wt% to about 50 wt % water.